| Abstract
| - We report a route for synthesizing patterned carbon nanotube (CNT) catalysts through the microcontact printingof iron-loaded poly(styrene-block-acrylic acid) (PS-b-PAA) micellar solutions onto silicon wafers coated with thinaluminum oxide (Al2O3) layers. The amphiphilic block copolymer, PS-b-PAA, forms spherical micelles in toluenethat can form quasi-hexagonal arrays of spherical PAA domains within a PS matrix when deposited onto a substrate.In this report, we dip a poly(dimethylsiloxane) (PDMS) molded stamp into an iron-loaded micellar solution to createa thin film on the PDMS features. The PDMS stamp is then put in contact with a substrate, and uniaxial compressivestress is applied to transfer the micellar thin film from the PDMS stamp onto the substrate in a defined pattern. Thepolymer is then removed by oxygen plasma etching to leave a patterned iron oxide nanocluster array on the substrate.Using these catalysts, we achieve patterned vertical growth of multiwalled CNTs, where the CNTs maintain the fidelityof the patterned catalyst, forming high-aspect-ratio standing structures.
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